Nuffield Department of Medicine, The Jenner Institute (ORCRB), University of Oxford , Oxford , UK.
Front Immunol. 2013 Jul 16;4:197. doi: 10.3389/fimmu.2013.00197. eCollection 2013.
CD4(+)Foxp3(+) regulatory T cells (Tregs) have a fundamental role in maintaining immune balance by preventing autoreactivity and immune-mediated pathology. However this role of Tregs extends to suppression of anti-tumor immune responses and remains a major obstacle in the development of anti-cancer vaccines and immunotherapies. This feature of Treg activity is exacerbated by the discovery that Treg frequencies are not only elevated in the blood of cancer patients, but are also significantly enriched within tumors in comparison to other sites. These observations have sparked off the quest to understand the processes through which Tregs become elevated in cancer-bearing hosts and to identify the specific mechanisms leading to their accumulation within the tumor microenvironment. This manuscript reviews the evidence for specific mechanisms of intra-tumoral Treg enrichment and will discuss how this information may be utilized for the purpose of manipulating the balance of tumor-infiltrating T cells in favor of anti-tumor effector cells.
CD4(+)Foxp3(+) 调节性 T 细胞 (Tregs) 通过防止自身反应和免疫介导的病理来在维持免疫平衡方面发挥着重要作用。然而，Tregs 的这种作用扩展到抑制抗肿瘤免疫反应，并且仍然是癌症疫苗和免疫疗法开发的主要障碍。Treg 活性的这一特征因以下发现而加剧：Treg 频率不仅在癌症患者的血液中升高，而且与其他部位相比，在肿瘤中也明显富集。这些观察结果引发了人们对理解 Tregs 在携带肿瘤的宿主中升高的过程以及确定导致它们在肿瘤微环境中积累的特定机制的探索。本文综述了肿瘤内 Treg 富集的特定机制的证据，并将讨论如何利用这些信息来操纵肿瘤浸润 T 细胞的平衡，以有利于抗肿瘤效应细胞。
